The Night Tube hasn't happened, indeed is now three months overdue, and as yet there are no convincing signs of any launch date whatsoever. Indeed there is a school of thought which thinks the Night Tube may never happen - it might fall to the next Mayor to scrap it - and all the savings could be ploughed back into more useful daytime services.

But the other pledge is most definitely on track. Every TfL ticket office is scheduled to close by the end of the year, that's within the next four weeks, with ticket windows covered up and staff moved out into public space. Typical, isn't it, the thing everybody wanted hasn't happened while the much less popular thing is almost complete.

Which begs the question, which will be the last TfL ticket office to close? It ought to be one of these.

In TfL's list of Ticket hall improvement and closure works: 2015, these are the 30 stations with a December deadline. No specific dates are given. TfL have been exceptionally reticent to reveal this key information until a fortnight beforehand, when a poster goes up in the ticket hall and an email is sent to regular users of the station. But one of these, or perhaps a joint-last group, should be the last to sell a ticket from behind a window. Which will it be?

Now it might not be one of these, because the list was last updated in August, because it's not in TfL's interest to provide the public with up-to-date information. Indeed I received an email only this week telling me that Whitechapel's ticket office will be closing on 14th December, and Whitechapel was scheduled to be a September finish. In a separate email I also learned that Canary Wharf goes ticket-office-free on 7th December, so I think we can cross that station off the list as well.

There was also some doubt over the future of ticket offices on tube lines shared with National Rail. Gunnersbury and Kew Gardens fall into this category, as do all the Bakerloo line stations from Queen's Park to Harrow and Wealdstone. Meanwhile certain tube stations aren't operated by Tfl at all, including Richmond, Barking and Upminster, so they're not on the imminent closure list either. But at least 30 stations are, and somewhere's got to be last.

We should combine our collective knowledge and researching power and to try and identify TfL's last ticket office. This might mean spotting it by crossing all the other stations off as their closure dates become known, and seeing what's left, or maybe somebody has some actual behind the scenes information. But we should absolutely definitely find the last one, and make sure its identity becomes widely known, and then all pop down on the last day to make a transaction. TfL appear to be smothering their last few ticket offices as quietly as possible, so we ought to point and shout and make a fuss. For posterity's sake, if not because anyone needs to buy a ticket.

(and IF that's true, then the last TfL ticket office to sell tickets will be Aldgate East, St James's Park or Upton Park on Friday evening next week)
(11 ex-Silverlink ticket offices on the Bakerloo and District lines will remain open into 2016 pending public consultation)